Small update of Colormap documentation
Small update of Colormap documentation

Small change in documentation: http://docs.opencv.org/master/d3/d50/group__imgproc__colormap.html#gga9a805d8262bcbe273f16be9ea2055a65a5d4a709cda1130bfa3cc4b4c5ae8f82a&gsc.tab=0

In the enum images, the "parula" colormap has wrongly assigned subtitle 'hot'
opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv